<?php
/**
 * Created by PhpStorm.
 * User: merlin
 * Date: 15-7-31
 * Time: 下午6:30
 */
class UUID
{
    /**
     * 生成UUID
     * @return string
     */
    static public function Create()
    {
        if (function_exists('com_create_guid')) {
            return trim(com_create_guid(), '{}');
        } else {
            mt_srand((double)microtime() * 10000);
            $charid = strtoupper(md5(uniqid(rand(), TRUE)));
            $hyphen = chr(45);
            $uuid   = substr($charid, 0, 8) . $hyphen
                . substr($charid, 8, 4) . $hyphen
                . substr($charid, 12, 4) . $hyphen
                . substr($charid, 16, 4) . $hyphen
                . substr($charid, 20, 12);

            return $uuid;
        }
    }
}